The man who killed a Calgary Centex employee during a gas-and-dash theft has asked the Alberta Court of Appeal to lower his 11-year sentence.​

Maryam Rashidi was run over by Joshua Mitchell in June 2015 as she tried to stop him from stealing $113 in fuel.

Originally charged with second-degree murder, Mitchell was convicted of manslaughter after a jury trial. He was sentenced to 11 years in prison: 10 for manslaughter and one for the hit-and-run conviction.

On Tuesday, defence lawyer Balfour Der argued before a panel of Alberta Court of Appeal judges that Mitchell's manslaughter sentence was too high.

Der said the trial judge punished Mitchell twice when he found Rashidi's death was an aggravating factor when his crime was that he caused her death. He also argued the judge should have taken into account Mitchell's youth and lack of a serious criminal record.​

Rashidi was working at the northwest gas station when she chased Mitchell — who was driving a stolen truck — down 16th Avenue.

She climbed on the truck's hood while it was stuck in traffic on 16th Avenue N.W. Mitchell tried to jostle her off but she eventually fell under the vehicle, which then drove over her, causing fatal injuries.

"The optics are bad," said Der of the crime. "But we don't just sentence strictly on the facts or the optics of a case."

Rashidi and her husband had moved to Calgary from Iran with their son for engineering jobs in the oil and gas industry, but were laid off after just four months.

She had taken the job at the Centex station to help make ends meet and was working just her fourth shift when she was killed.

Just weeks after Mitchell was convicted, while travelling to Calgary to mark the two-year anniversary of his wife's death, Ahmad Nourani Shallo was killed in a car accident, leaving his eight-year-old son an orphan.

Mitchell is also appealing his lifetime driving prohibition.

Prosecutor Brian Graff told the judges Mitchell's sentence fit the "terrible and violent crime."

The panel has reserved its decision.